The present invention relates generally to turning machines such as lathes or the like and more particularly a face and internal turning head for such a machine having a cylindrical drive device which is equipped with a fixing pin and which is adapted to be secured to the front face of the work spindle of a cutting machine. A tool slide that is frontally positioned on the drive means and is radially displaceable by means of a planetary power split transmission surrounding the drive means. For the displacement movement of the tool slide it is possible to superimpose on the hydrostatic power split transmission a rotary movement produced by a motor.
Numerous different constructions of face and internal turning heads are known. They are constructed as attachments for machining units, i.e. for conventional milling machines, boring mills and standard components enabling lathe work to be carried out, which requires a feed movement at right angles to the work spindle rotation axis. If the work spindle is mounted in a spindle sleeve or displacement slide, the face and internal turning head can perform an independent longitudinal movement, so that the head can not only be used for facing, but also for drilling or boring work involving large diameters.
Whereas in the case of simple face and internal turning heads, the displacement of the tool supported on the tool slide is performed manually, an automatic radial displacement of the tool with respect to the drive spindle axis performable automatically with a control means is also known (DE-OS No. 21 43 924 and European patent application No. 54 838). However, it is a disadvantage of both known constructions, that a drive motor must be housed in the machine casing and this is controlled by a control system, e.g. a digitally controlled means. This requires a relatively large volume of space, which is not normally available, particularly in the case of the spindle sleeve mounting of the drive spindle. It is therefore difficult to use the known face and internal turning heads for the turning of large bores.